//產生一個chirp子脈沖步進頻信號



#include <math.h>
double y[10000];

void steppedchirp(double f0,int n,int N,double Tr,double k,double T,double a,double fs)/*f0載頻，k調頻斜率，Tr取樣周期，T脈寬，a幅度，n一周期內取樣點數，N一周期子脈沖個數*/
	{		
	    	int i,m;
		double x,pi;
		pi=3.14159;
		double rect; 
		for(m=0;m<N;m++)
			{
				for(i=0;i<n;i++)
			 	{
			     		x=i/fs;
			     		if(x<=T&&x>=0)
				 	rect=a;
				 	else rect=0;
 		       			y[n*m+i]=rect*cos(2*pi*(f0+m*df)*x+pi*k*x*x);
		       		}	
			}
		          	 


	}

main()
	{
	    	int n,N;
		double Tr,f0,k,T,a,B,fs;
		B=7e+7;//子脈沖帶寬
		fs=1e+8;
		Tr=4e-5;
		n=2300;
		f0=9.6e+10;
		T=2e-5;
		k=B/T;
		a=1;
		N=3;
		steppedchirp(f0,n,N,Tr,k,T,a,fs);
	}